High-Pressure Treatment up to 25~GPa of Czochralski Grown Si Samples Containing Different Admixtures and Defects

The thermoelectric properties of a set of single crystalline Si wafers with different oxygen concentration grown by the Czochralski technique have been studied at ultrahigh pressures up to 25 GPa. The dependence of semiconductor-metal transition pressure at Czochralski grown Si on the concentration c_{O} of the interstitial oxygen was found to present a convex curve with the maximum near c_{O} ≈ 9 × 10^{17} cm^{-3}. The high pressure thermoelectric power method seems to be suitable for characterization of impurity-defect structure of Si wafers. For Si_{1 - x}Ge_{x} crystals (1% < x < 3%) the strong changes of both the value and the sign of thermoelectric power have been observed at pressures much less than ones of Si-I → Si-II transition. From nanoindentation data the phase transition Si-I → Si-II, corresponding to semiconductor-metal electronic transformation has been detected at the loading up to ≈ 10 mN. These findings suggest a way for creation of integrated circuits, in which zones with different types of conductivity and hence different p-n, p-n-p etc. structures may be "written" by applied stress at nanoscale level, and the control on the value of the above stresses now is possible by the proposed nanoindentation technique.